Fitness tracker



FIG. 1 is a top side isometric view of a fitness tracker;

FIG. 2 is a bottom side isometric view thereof;

FIG. 3 is a front side elevation view thereof;

FIG. 4 is a back side elevation view thereof;

FIG. 5 is a left side elevation view thereof;

FIG. 6 is a right side elevation view thereof;

FIG. 7 is a top plan view thereof; and,

FIG. 8 is a bottom plan view thereof.

The features shown in dash-dash lines in the drawing depict portions of the fitness tracker and form no part of the claimed design. 

CLAIM The ornamental design for a fitness tracker, as shown and described. 